ABORTION
Early complications and late sequelae of induced abortion: a review of the literature KARIN G. B. EDSTROM 1 An attempt to evaluate the recent literature on somatic complications of induced abortion shows that a great amount of data of widely varying quality has been collected. Many areas of research are still not covered in a way that permits valid conclusions to be drawn. Two important points emerge from the review: first, there is a need for uniform definitions of complications and some uniformity in the analysis of data collected; secondly, carefully selected control groups are needed in this kind of research. The areas most urgently requiring further study differ from country to country. From a global point of view, the existence or inexistence of significant late sequelae and the influence of the patient's health status on the complication rate seem to be of the highest priority.
Legislation permitting the performance of abortion on other than strictly medical grounds varies among countries, as does the application of existing laws. The general trend is, however, towards a liberalization of current laws and attitudes. Thus, there is an increased demand on clinical scientists to provide reliable and unbiased data on possible adverse effects of induced abortions-data that are essential for policy makers and health administrators. This review of the recent literature concerning somatic aspects of induced abortion brings together some of the more valid information concerning the incidence of complications and attempts to evaluate the factors influencing their frequency. It also identifies some of the areas in which further studies and research are required. There are obvious difficulties in comparing data from different authors; ways of collecting data and definitions of complications differ immensely. The frequent lack of adequate control groups and the sometimes obvious prejudices of the author make it difficult to draw conclusions. The papers reviewed have been selected to cover the various aspects of early complications and late sequelae of abortion as completely as possible and yet to avoid the difficulties mentioned above. 1 Research Physician, WHO Research and Training Centre, Karolinska Hospital, Stockholm, Sweden (present address: Medical Officer, Maternal and Child Health, World Health Organization, 1211 Geneva 27, Switzerland). 3332
TOTAL MORTALITY AND MORBIDITY RATES
Mortality Reasonably accurate country statistics are available only for the United Kingdom, USA (New York State), the Scandinavian countries, and some countries in eastern Europe (1-5, 7). Those rates are listed in Table 1. For USA, the only material that is large enough to provide sufficiently reliable data on mortality is that relating to New York State since the new Abortion Act was passed in July 1970 (3). A rate for Japan, based on reported deaths attributed to legal abortion and on reported legal abortions, has been calculated by Tietze (2). The fact that the proportion of unreported abortions in Japan is unknown detracts from the accuracy of calculations for that country, but Tietze's calculated rates for the periods 1950-53 and 1954-58 (8.5 and 5.8 deaths per 100 000 abortions, respectively) correspond rather well to that quoted by Muramatsu (8) from a 1954 survey including 108 055 cases with a mortality of 7.4 per 100 000 abortions. The figures from Korea estimated by Hong (7) are included for comparison, since induced abortion (even outside hospital) is considered to be performed almost exclusively by specialists in obstetrics and gynaecology. The mortality for different methods has been analysed for 402 000 abortions performed in New York in 1970-72 (3). Uterine aspiration had the lowest rate, 1.1 deaths per 100 000 abortions, dilatation and curettage came next with 2.4, and saline
- 123 -
BULL. WORLD HEALTH ORGAN., Vol. 52, 1975
124
KARIN G. B. EDSTROM
Table 1. Mortality due to induced abortion in several countries Country
Mortality per
Hungary
1964-67
1.2
Czechoslovakia
1963-67
2.5
Yugoslavia (Slovenia)
1961-67
5.7
Japan USA (NY)
1959-65 1970-72 1970
4.1 12
1965-69
13
United Kingdom (England and Wales) Sweden Korea (Seoul)
1967
5
60-125 (estimated)
instillation in 53 000 cases had a rate of 18.8. Hysterotomy shows a very high death rate-5 for 2 400 abortions, or 208 per 100 000-but this might be due partly to factors such as health status and age (see below). In the United Kingdom in 1969, the reported mortality for 31 000 uterine aspirations or dilatations and curettages before the 13th week was 6 per 100 000. For 3 700 first-trimester hystero-
Reference No.
Source of information
100 000 abortions
Period
David, 1970 David, 1970 David, 1970
(1) (1)
(1)
(2) (3) (4)
Tietze, 1971 Tietze et al., 1973 Office of Population Censuses and Surveys, 1973 National Health Board, 1972 Hong, 1970
(5) (7)
tomies it was 80 per 100 000, and for secondtrimester hysterotomies 90 deaths per 100 000 abortions (9).
Morbidity The morbidity rates associated with induced abortions (Table 2) also vary substantially among the different countries (5, 6, 10-19) but not to the same
Table 2. Morbidity rates associated with induced abortion in various countries and with different methods of collecting data Country USA (NY City residents) USA (Hawaii) Czechoslovakia Hungary (Budapest) Denmark United Kingdom (England and Wales) USA (JPSA study)
Period
July 1970-March 1971 4 months, 1970
1963
1960-69 1961-66 1969
July 1970-June 1971
Hungary (Budapest) Poland (Warsaw) Sweden
1966 1958-68
United Kingdom
1967-70
Czechoslovakia
1968
a
1964
Major complications.
b Total complications.
Method of collecting data
reports to Department of Health reports on 1 169 cases
Moorbidityper I 00 abortions 1.0
Pakter E Nelson, 1971
(10)
4.1
Smith et al., 1971
2.3
Mehlan, 1969 Czeizel & Bognar, 1971 Olsen et al., 1971 Huntingford, 1971
(11) (12) (13) (6) (14)
Tietze E Lewit, 1972
(15)
Bognar, 1969
(16) (17) (5)
reports to Department of Health reports to Ministry of Health reports to Ministry of Health
4.7
reports to Ministry of Health
3.4
survey with follow-up of 73 000 cases survey of 55 000 cases survey of 3482 cases survey of 1 427 cases
survey of 1 317 National Health Service cases 'informal estimation
by gynaecologists"
n~~~No. Source of information abNo
2.6
1.0-1.6 a 9.6-13.1 b 7.3 8.4 18.5
Sternadel et al., 1968 1965 Committee on
16.8
Abortion, 1971 Sood, 1971
15.0
Kuck, 1969
(18) (19)
125
ABORTION
Table 3. Early complications occurring in connexion with uterine aspiration and with dilatation and curettage. Number of different complications per 100 abortions Incomplete evacuation
Proain Perforation
Cervical trauma
0.8-5.0
0.5-10.4
0.03-1.7
0.03-4.9
1.5
-
0.3
0.9
Total
Study
complication
range of complication rates a in literature reviewed
0.8-7.3
rate
Bleeding
Infection
Uterine aspiration -
total complications
4.7
major complications
Vladov et al. (28)
0.5 5.2
66 ml b
1.6
-
-
-
Jurukovski & Sukarov (23)
3.9
-
1.13
1.82
0.03
0.03
Lunow et al. (26)
-
-
0.3
0.9
-
1.0 C -
-
Beric & Kupresanin (21)
-
1.3
0.4
-
0.7-3.8
0.12-2.1
0.16-3.9
3.5
-
-
-
1.65
1.60
JPSA (15)
range of complication rates a in literature reviewed P total complications J PSA (1 5) I major complications
1.2
(incl. fever only)
Dilatation and curettage 5.4-15.3 0.87-55.6 (5-10) d
6.7
0.6 85 ml b
Vladov et al. (28)
9.0
Jurukovski & Sukarov (23)
4.8
-
Lunow et al. (26)
-
2.1 c
Beric & Kupresanin (21)
-
-
0.03
0.16
-
-
2.1
3.9
-
3.8
0.12
-
Includes authors under references Nos 6, 15, 18 and 20-29. Mean blood loss (300 cases with uterine aspiration, 280 with dilatation and curettage). Percentage of patients requiring transfusion. d Range of most studies reviewed. a
b c
extent as mortality rates, and the manner in which data are collected plays a much more important role. Czeizel & Bognar (13) compare the complication rate in Budapest based on reports to the Office of Statistics during the period 1960-69 with that found in a survey of 55 000 cases in that city during 1966. They find a reported rate of 2.6%, whereas the survey showed that 4.2 % were treated in hospital for complications resulting from abortion. Bognar (16) adds complications registered in outpatients, giving a total morbidity of 7.3% for the 1966 survey. An even more pronounced difference is seen during identical periods in USA between morbidity in New York City based on reports and morbidity in the JPSA a study including follow-up. The different ways of defining morbidity and complications account for some of the differences shown in Table 2, but this factor is probably more important when one tries to interpret and compare a Joint Program for the Study on Abortion, see Tietze & Lewit (15).
data such as those reviewed in the following sections. Gestational stage at abortion, parity, and health status are important factors influencing morbidity, and they will be dealt with separately later. EARLY COMPLICATIONS IN RELATION TO THE METHOD USED
First-trimester abortions
These are performed, almost without exception, either by " classical curettage " (dilatation and curettage) or by suction curettage, otherwise known as uterine aspiration. Both methods have a low total complication rate (Table 3) compared with secondtrimester abortions, but the range of complications reported by different authors varies markedly, as do their definitions of complications (6, 15, 18, 20-29). Prospective studies with direct comparison of the methods (15, 28) show somewhat superior results for uterine aspiration but perhaps not such a pro-
126
KARIN G. B. EDSTROM
Table 4. Complication rates (No. per 100 abortions) and deaths associated with intrauterine saline infusion Study
JPSA, Tietze & Lewit (33), USA Bengtsson (34), Sweden:
Total rate of No. of deaths No. of patients complications 14 690
23.4 (major 1.7)
3a
Bleeding
Infections
17.2
4.8
intra-amniotic
2 797
-
2b
extra-amniotic Olsen et al. (6), Denmark Kerenyi et al. (35), USA
3364 6940 5000
-
1 c
5.0 e 7.8 e
4.5
3d
-
-
0
2.3
1.6 f
2.3f
a One patient (schizophrenic) committed suicide one month after the abortion; one developed hypernatraemia, convulsions, and renal failure. The third died from severe haemorrhage after partial separation of the placenta. b One probably related to intravenous injection; one cardiac arrest in a patient with congenital heart disease. c Septicaemia. d One patient died 13 days after abortion as a result of laparotomy for sterilization. e Percentage of patients requiring transfusion. f Symptoms of pelvic infection.
nounced difference as has sometimes been claimed (24). Bleeding is usually not an extensive problem with first-trimester abortions (Table 3). Sometimes, however, it has been reported in a very high proportion of cases, usually combined with a high proportion of operations beyond the 12th week. Thus, Stallworthy et al. (27) in almost 800 cases terminated by uterine aspiration, report a blood loss of 500 ml or more in 17 % and haemorrhage requiring transfusion in 8 %. Infection shows the same distribution as the total complication rate. The very wide range reflects the great differences in the definition of infection, ranging from a temperature of 37.5°C to peritonitis. Incomplete evacuation of the uterus is the only complication reported slightly more often with uterine aspiration (24, 28, 30). Beric & Kupresanin (21) find the reverse to be true, but their two series are for different time periods and received different types of anaesthesia. Perforation of the uterus is infrequent, especially when uterine aspiration is used for induced abortion in countries with a high abortion load (21, 23, 26). In England several clinics using mainly this method (up to at least 14 weeks) report a perforation rate of 0.5-2.7% (18, 25, 27). Stallworthy et al. (27), during abdominal tubal ligation after uterine aspiration, found previously undiagnosed perforations in 3 patients. Treatment is usually laparotomy and repair or hysterectomy, but conservative treatment is often
successfully applied. In the JPSA study (15), of the 187 perforations reported 88 were handled successfully with conservative treatment. Cervical trauma parallels perforation, and is usually reported 3-5 times as frequently (15, 23, 26). Trauma to the uterine myometrium, defined as smooth muscular tissue found during histological analysis of scrapings from the uterine cavity, is frequently reported with dilatation and curettage, and Andreev (31) reports " deep injury to the muscular wall" (in his opinion carrying a serious risk of intrauterine adhesions) to be 38 times as frequent during dilatation and curettage as during uterine aspiration.
Second-trimester abortions Intrauterine instillation ofhypertonic solutions. The most extensive experience with this method so far has been in Scandinavia and lately in USA. In Japan it was formerly used extensively but not always with safety precautions, and the method has now been abandoned there because of high complication rates (32). The complication rates found in the JPSA study (33), a retrospective survey by Bengtsson (34), a consecutive series of 5 000 saline abortions by Kerenyi et al. (35), and an analysis of reports to the Danish Medical Health Board (6) are shown in Table 4. Bleeding is a much more frequent complication here than with first-trimester abortions. In Bengts-
ABORTION
son's study, which was based on an inquiry in all Swedish centres performing induced abortions, haemorrhage was said to have occurred when the patient received a blood transfusion. The fairly high rate of this complication probably reflects a generous attitude in Sweden towards replacing blood loss, but on the other hand there is evidence of a frequent decrease in coagulation factors after intra-amniotic saline instillations in otherwise uneventful cases (36-39). Infection is less common than haemorrhage, but is more frequently seen than with first-trimester methods (5, 33, 34). The incidence of infection following instillation of hypertonic glucose is usually higher than that following saline (5, 40). Retention of placental tissue is reported at extremely varying rates, owing to different attitudes of operating clinics. In many cases curettage is performed routinely after abortion. The failure rate is dependent to a great extent on the patience of doctors and patients but also on the solution used, the technique applied, etc. (discussed below). Schulman et al. (96), in inducing abortion by intrauterine saline injection in 323 outpatients, experienced only one failure (with a living fetus 3 weeks later), but 13 patients took more than a week to abort. Bengtsson (34) reports a rate of 96.5 % aborting after the first intra-amniotic instillation and 85.1 % after the first extra-amniotic instillation. The efficiency rate for the first intra-amniotic instillation in the JPSA study (15) was 95.5 %. Kerenyi et al. (35) give a corresponding figure of 98.6% success for the first instillation and 0.4% total failure for the last 1 000 patients in their series. Glucose is less efficient and failure rates of 15-22 % are reported (27). Symptoms of intravasal injection of hypertonic saline, sometimes combined with amnion embolism, are evident in a large proportion of case reports (6, 32, 34, 41, 42). The frequency of accidental transfusion is not known, but Gustavii (43), in 10 of 69 extra-amniotic instillations, by adding roentgen contrast medium could prove an immediate shift of fluid into the veins. Intravasal haemolysis (36), hypernatraemia (43, 44), and changes in blood volume (42, 44) have been seen, but marked changes seem to occur only in connexion with symptoms of intravenous injection. Hysterotomy and hysterectomy in the JPSA study (15), showed the highest complication rates of all methods: 38.0% and 51.2%, respectively; yet Olsen et al. (6) reported a complication rate of only 2.5 % for hysterotomy and sterilization in 6 544 cases.
127
However, all authors (6, 15, 18, 45) agree that the complications are definitely more serious. The reported incidence rates of " major " complications in connexion with hysterotomy and hysterectomy in local a JPSA patients are 9.4% and 17.1 %, respectively, compared with a total incidence of major complications of 1.6%. Vaginal hysterotomy, according to Lindahl (46), had a low immediate complication rate, but he found endometriosis in the scar in 19.8% of 840 follow-up cases. Other methods, such as soap, Utus paste, urea instillations, bougies, laminaria tents, and Rivanol, are used in some countries to a considerable extent but are usually very poorly reported, and the complication rates are difficult to estimate. For the period 1961-66, Olsen et al. (6) report 1 275 cases aborted with cremor saponis and a complication rate of 9.1 %-the highest produced by any method used in their series-and most European and American authors agree that the complications arising with the above-mentioned methods are more alarming (6, 45, 47-51). Rivanol 0.1 % given by extra-amniotic instillation is possibly more promising. The abortive effect is about the same as that of saline, it has a slight oxytocic effect in vitro (52), and the incidence of infection seems to be low (49, 52). It is claimed to be atoxic (used as a bladder disinfectant) and actually many of the fetuses are aborted alive. However, Pytel et al. (53) cite 4 cases of renal failure possibly related to the instillation of this solution. The numerous research projects on prostaglandins for the induction of abortion have been concerned mainly with the mechanisms of action and the effectiveness of various routes of administration. However, the substances also have pronounced systemic effects when administered by the intravenous, route. Anderson & Speroff (54) in a tolerance study infused PGF2a in doses of 25-200 jig/min in 10 patients. The incidence of nausea, vomiting, and diarrhoea was 90 %, 5 patients developed some degree of diastolic hypertension during infusion, and another developed a severe vasovagal shock and bradycardia lasting 45 min after the infusion was stopped. The techniques at present under investigation do not involve the intravenous route of administration. The intra-amniotic or extra-amniotic instillation of small amounts of prostaglandins (55-57) have increased the success rate and decreased the occurrence of side effects such as those mentioned above. a
Excluding patients residing outside the service area.
128
KARIN G. B. EDSTROM
The Task Force on the use of Prostaglandins for Regulation of Fertility is now working on finding the best techniques and compounds for induction of abortion. LATE SOMATIC SEQUELAE TO INDUCED ABORTION
A large number of late sequelae have been attributed to induced abortion, without any proved cause-relationship. Some sequelae have been studied more thoroughly than others-mostly those related either to the woman's ability to conceive after abortion or to the outcome of her subsequent pregnancies. Wynn & Wynn (58) in 1972 published a review on the side effects of induced abortion, containing a large part of all statements made against it and studies with adverse findings. This article has been much discussed in the United Kingdom and, among others, Trussell (59) and Potts & Shadbolt (60) have admirably pointed out the pitfalls in their reasoning. No gynaecologist who has performed an induced abortion ever tries to deny that it can give rise to early or late complications. But every gynaecologist also knows-which Wynn & Wynn seem to forget-that all other terminations of pregnancy, such as delivery or spontaneous abortion, also can produce the same type of complication. Furthermore, the fact that the woman applying for abortion is already pregnant must be accepted and taken into account when complications are discussed. All studies without adequate control groups (which here means comparable as regards both the previous number of pregnancies and the health and nutritional status) will show only that there are complications and not whether this way of terminating the pregnancy is more dangerous than letting it terminate by itself (or by clandestine abortion). This is unfortunately true of most retrospective studies published on this problem. Studies on psychiatric or emotional sequelae of induced abortion are not discussed in this paper. Such sequelae are too dependent upon national legislation and social attitudes to permit meaningful comparison of studies from different countries. The somatic sequelae most seriously investigated are discussed below. Reduced fecundity. Retrospective studies have sometimes blamed induced abortion as the cause of infertility (61, 62). However, Hayashi & Momose (63) compared a group of women complaining of secondary infertility with a group of multigravidae
delivered at full term and found no difference between the two groups in the proportion of women having experienced an abortion. The only exception was seen among those having experienced only one previous pregnancy, where the percentage of induced abortion among infertile women was 41.1 and that in the control group 32.6-a high incidence of aborted primigravidae also in the control group. In prospective studies by Lindahl (46), mainly involving vaginal hysterotomy, and by Jiratko et al. (64), probably covering primarily uterine aspiration, no definite evidence of reduced fecundity could be found. Premature births and spontaneous abortions in retrospective studies from Japan (65) occurred more frequently in women with previous induced abortions, among patients with premature deliveries, spontaneous abortions, or habitual abortions, than in control groups with full-term deliveries, but the latter were not matched according to age, social group, or parity. The same is true for Dol6zal et al. (66), who found a significantly higher proportion of previous induced abortions among 189 mothers with premature deliveries than in a control group of 197 women delivered of full-term babies. Other clinical studies also have shown an increased risk of premature delivery or second-trimester abortion after an induced abortion (67-69), but the control groups are usually never matched for both parity and health status, and it remains to be shown whether this increase is caused by the abortion procedure, by factors hidden in the decision to interrupt the pregnancy, or by both. Data from Hungary, where the incidence of low birth-weight is the highest in Europe, as is the incidence of abortion, seem to indicate that other factors also play an important role. In a survey in 1970 (70) they found that the rate of live-born babies weighing less than 2.5 kg increased with the number of previous induced abortions, there being a 100 % increase with 0-2 previous abortions and 200% at 4 abortions. However, the proportion of women with premature delivery but no previous abortion was also very high: 10.1 %, and the total percentage was 11.8. There was a successive increase from the 1960 percentages, but this was true also for women with no previous abortions, 8 % of whom that year had babies weighing less than 2.5 kg. During the same time the proportion of still births decreased at approximately the same rate as that of babies with low birth-weight increased. The Hungarian perinatal mortality study (71) showed the proportion with low
ABORTION
birth-weight to be higher in manual workers and in smokers than in nonmanual workers and nonsmokers, and the effect of these factors was apparently of at least the same magnitude. An increased frequency of extrauterine pregnancies has been mentioned by several authors, mainly from eastern Europe (30, 61, 72, 73). Cernoch (73) analyses the change in the numbers of ectopic pregnancies, induced abortions, and deliveries in Czechoslovakia in 1955-68, and he claims an increase in the former, parallel with the increase in induced abortions. During the years 1964-68, however, there is a decrease in the number of ectopic pregnancies in spite of a stable total number of pregnancies and a slight increase in induced abortions. Beric & Kupresanin (21) find, in Novi Sad from 1960 to 1970, an increase in the birth rate and in induced abortions but a relative decrease in the number of extrauterine pregnancies. Kur6iev et al. (72) report that 48.2% of the patients treated for extrauterine pregnancies in Skopje in 1967-68 had a previous induced abortion, but do not mention the abortion ratio in the population. Sawasaki & Tanaka (74), in 222 cases of extrauterine pregnancy among Japanese women, find that the preceding pregnancy was terminated by induced abortion in 43.8%, which does not differ significantly from the 50.2% found in a control group. The complication rate in subsequent pregnancies and deliveries, i.e., full-term deliveries, is also claimed to be affected by previous abortion. Thus, Lembryck (69), in his group of 143 primiparae (second gravidae) with a previous interrupted pregnancy, finds a higher frequency of bleeding during pregnancy and delivery and a somewhat longer first stage of labour, but a lower rate of toxaemia and no difference in the numbers of spontaneous deliveries. His control group consisted of 143 primiparae, primigravidae. Atanasov et al. (75) found 67.5% complicated pregnancies or deliveries in 265 women with previous abortions, compared with 13.4% in 418 with no previous abortion, the main complications being bleeding and toxaemia. He does not give data on parity in the two groups. Czeizel & Bognar (13), in a preliminary analysis of legal abortions in Hungary, found a rising incidence of deliveries complicated by placenta praevia and abruptio placentae that to some extent paralleled the rise in abortions. On the other hand, Heczko et al. (76) studied 173 parturient women who had had their first pregnancy terminated by abortion, and they found the same rate of late pregnancy and delivery complications
129
and the same perinatal mortality as among 18 226 other parturients during the same period. Furusawa & Koya (77) compared a large group of women terminating their first pregnancy by induced abortion and their second pregnancy by delivery with a control group of primiparae, primigravidae, matched for age and civil status. They found so significant difference in birth-weight, rate of instrumental deliveries, amount of bleeding, or length of the third stage of labour, although possibly a moderate increase in the length of the first and second stages in the group with previous abortions. Doleial et al. (66) did not find previous abortion more often in mothers giving birth to small-for-date children (
Early complications and late sequelae of induced abortion: a review of the literature KARIN G. B. EDSTROM 1 An attempt to evaluate the recent literature on somatic complications of induced abortion shows that a great amount of data of widely varying quality has been collected. Many areas of research are still not covered in a way that permits valid conclusions to be drawn. Two important points emerge from the review: first, there is a need for uniform definitions of complications and some uniformity in the analysis of data collected; secondly, carefully selected control groups are needed in this kind of research. The areas most urgently requiring further study differ from country to country. From a global point of view, the existence or inexistence of significant late sequelae and the influence of the patient's health status on the complication rate seem to be of the highest priority.
Legislation permitting the performance of abortion on other than strictly medical grounds varies among countries, as does the application of existing laws. The general trend is, however, towards a liberalization of current laws and attitudes. Thus, there is an increased demand on clinical scientists to provide reliable and unbiased data on possible adverse effects of induced abortions-data that are essential for policy makers and health administrators. This review of the recent literature concerning somatic aspects of induced abortion brings together some of the more valid information concerning the incidence of complications and attempts to evaluate the factors influencing their frequency. It also identifies some of the areas in which further studies and research are required. There are obvious difficulties in comparing data from different authors; ways of collecting data and definitions of complications differ immensely. The frequent lack of adequate control groups and the sometimes obvious prejudices of the author make it difficult to draw conclusions. The papers reviewed have been selected to cover the various aspects of early complications and late sequelae of abortion as completely as possible and yet to avoid the difficulties mentioned above. 1 Research Physician, WHO Research and Training Centre, Karolinska Hospital, Stockholm, Sweden (present address: Medical Officer, Maternal and Child Health, World Health Organization, 1211 Geneva 27, Switzerland). 3332
TOTAL MORTALITY AND MORBIDITY RATES
Mortality Reasonably accurate country statistics are available only for the United Kingdom, USA (New York State), the Scandinavian countries, and some countries in eastern Europe (1-5, 7). Those rates are listed in Table 1. For USA, the only material that is large enough to provide sufficiently reliable data on mortality is that relating to New York State since the new Abortion Act was passed in July 1970 (3). A rate for Japan, based on reported deaths attributed to legal abortion and on reported legal abortions, has been calculated by Tietze (2). The fact that the proportion of unreported abortions in Japan is unknown detracts from the accuracy of calculations for that country, but Tietze's calculated rates for the periods 1950-53 and 1954-58 (8.5 and 5.8 deaths per 100 000 abortions, respectively) correspond rather well to that quoted by Muramatsu (8) from a 1954 survey including 108 055 cases with a mortality of 7.4 per 100 000 abortions. The figures from Korea estimated by Hong (7) are included for comparison, since induced abortion (even outside hospital) is considered to be performed almost exclusively by specialists in obstetrics and gynaecology. The mortality for different methods has been analysed for 402 000 abortions performed in New York in 1970-72 (3). Uterine aspiration had the lowest rate, 1.1 deaths per 100 000 abortions, dilatation and curettage came next with 2.4, and saline
- 123 -
BULL. WORLD HEALTH ORGAN., Vol. 52, 1975
124
KARIN G. B. EDSTROM
Table 1. Mortality due to induced abortion in several countries Country
Mortality per
Hungary
1964-67
1.2
Czechoslovakia
1963-67
2.5
Yugoslavia (Slovenia)
1961-67
5.7
Japan USA (NY)
1959-65 1970-72 1970
4.1 12
1965-69
13
United Kingdom (England and Wales) Sweden Korea (Seoul)
1967
5
60-125 (estimated)
instillation in 53 000 cases had a rate of 18.8. Hysterotomy shows a very high death rate-5 for 2 400 abortions, or 208 per 100 000-but this might be due partly to factors such as health status and age (see below). In the United Kingdom in 1969, the reported mortality for 31 000 uterine aspirations or dilatations and curettages before the 13th week was 6 per 100 000. For 3 700 first-trimester hystero-
Reference No.
Source of information
100 000 abortions
Period
David, 1970 David, 1970 David, 1970
(1) (1)
(1)
(2) (3) (4)
Tietze, 1971 Tietze et al., 1973 Office of Population Censuses and Surveys, 1973 National Health Board, 1972 Hong, 1970
(5) (7)
tomies it was 80 per 100 000, and for secondtrimester hysterotomies 90 deaths per 100 000 abortions (9).
Morbidity The morbidity rates associated with induced abortions (Table 2) also vary substantially among the different countries (5, 6, 10-19) but not to the same
Table 2. Morbidity rates associated with induced abortion in various countries and with different methods of collecting data Country USA (NY City residents) USA (Hawaii) Czechoslovakia Hungary (Budapest) Denmark United Kingdom (England and Wales) USA (JPSA study)
Period
July 1970-March 1971 4 months, 1970
1963
1960-69 1961-66 1969
July 1970-June 1971
Hungary (Budapest) Poland (Warsaw) Sweden
1966 1958-68
United Kingdom
1967-70
Czechoslovakia
1968
a
1964
Major complications.
b Total complications.
Method of collecting data
reports to Department of Health reports on 1 169 cases
Moorbidityper I 00 abortions 1.0
Pakter E Nelson, 1971
(10)
4.1
Smith et al., 1971
2.3
Mehlan, 1969 Czeizel & Bognar, 1971 Olsen et al., 1971 Huntingford, 1971
(11) (12) (13) (6) (14)
Tietze E Lewit, 1972
(15)
Bognar, 1969
(16) (17) (5)
reports to Department of Health reports to Ministry of Health reports to Ministry of Health
4.7
reports to Ministry of Health
3.4
survey with follow-up of 73 000 cases survey of 55 000 cases survey of 3482 cases survey of 1 427 cases
survey of 1 317 National Health Service cases 'informal estimation
by gynaecologists"
n~~~No. Source of information abNo
2.6
1.0-1.6 a 9.6-13.1 b 7.3 8.4 18.5
Sternadel et al., 1968 1965 Committee on
16.8
Abortion, 1971 Sood, 1971
15.0
Kuck, 1969
(18) (19)
125
ABORTION
Table 3. Early complications occurring in connexion with uterine aspiration and with dilatation and curettage. Number of different complications per 100 abortions Incomplete evacuation
Proain Perforation
Cervical trauma
0.8-5.0
0.5-10.4
0.03-1.7
0.03-4.9
1.5
-
0.3
0.9
Total
Study
complication
range of complication rates a in literature reviewed
0.8-7.3
rate
Bleeding
Infection
Uterine aspiration -
total complications
4.7
major complications
Vladov et al. (28)
0.5 5.2
66 ml b
1.6
-
-
-
Jurukovski & Sukarov (23)
3.9
-
1.13
1.82
0.03
0.03
Lunow et al. (26)
-
-
0.3
0.9
-
1.0 C -
-
Beric & Kupresanin (21)
-
1.3
0.4
-
0.7-3.8
0.12-2.1
0.16-3.9
3.5
-
-
-
1.65
1.60
JPSA (15)
range of complication rates a in literature reviewed P total complications J PSA (1 5) I major complications
1.2
(incl. fever only)
Dilatation and curettage 5.4-15.3 0.87-55.6 (5-10) d
6.7
0.6 85 ml b
Vladov et al. (28)
9.0
Jurukovski & Sukarov (23)
4.8
-
Lunow et al. (26)
-
2.1 c
Beric & Kupresanin (21)
-
-
0.03
0.16
-
-
2.1
3.9
-
3.8
0.12
-
Includes authors under references Nos 6, 15, 18 and 20-29. Mean blood loss (300 cases with uterine aspiration, 280 with dilatation and curettage). Percentage of patients requiring transfusion. d Range of most studies reviewed. a
b c
extent as mortality rates, and the manner in which data are collected plays a much more important role. Czeizel & Bognar (13) compare the complication rate in Budapest based on reports to the Office of Statistics during the period 1960-69 with that found in a survey of 55 000 cases in that city during 1966. They find a reported rate of 2.6%, whereas the survey showed that 4.2 % were treated in hospital for complications resulting from abortion. Bognar (16) adds complications registered in outpatients, giving a total morbidity of 7.3% for the 1966 survey. An even more pronounced difference is seen during identical periods in USA between morbidity in New York City based on reports and morbidity in the JPSA a study including follow-up. The different ways of defining morbidity and complications account for some of the differences shown in Table 2, but this factor is probably more important when one tries to interpret and compare a Joint Program for the Study on Abortion, see Tietze & Lewit (15).
data such as those reviewed in the following sections. Gestational stage at abortion, parity, and health status are important factors influencing morbidity, and they will be dealt with separately later. EARLY COMPLICATIONS IN RELATION TO THE METHOD USED
First-trimester abortions
These are performed, almost without exception, either by " classical curettage " (dilatation and curettage) or by suction curettage, otherwise known as uterine aspiration. Both methods have a low total complication rate (Table 3) compared with secondtrimester abortions, but the range of complications reported by different authors varies markedly, as do their definitions of complications (6, 15, 18, 20-29). Prospective studies with direct comparison of the methods (15, 28) show somewhat superior results for uterine aspiration but perhaps not such a pro-
126
KARIN G. B. EDSTROM
Table 4. Complication rates (No. per 100 abortions) and deaths associated with intrauterine saline infusion Study
JPSA, Tietze & Lewit (33), USA Bengtsson (34), Sweden:
Total rate of No. of deaths No. of patients complications 14 690
23.4 (major 1.7)
3a
Bleeding
Infections
17.2
4.8
intra-amniotic
2 797
-
2b
extra-amniotic Olsen et al. (6), Denmark Kerenyi et al. (35), USA
3364 6940 5000
-
1 c
5.0 e 7.8 e
4.5
3d
-
-
0
2.3
1.6 f
2.3f
a One patient (schizophrenic) committed suicide one month after the abortion; one developed hypernatraemia, convulsions, and renal failure. The third died from severe haemorrhage after partial separation of the placenta. b One probably related to intravenous injection; one cardiac arrest in a patient with congenital heart disease. c Septicaemia. d One patient died 13 days after abortion as a result of laparotomy for sterilization. e Percentage of patients requiring transfusion. f Symptoms of pelvic infection.
nounced difference as has sometimes been claimed (24). Bleeding is usually not an extensive problem with first-trimester abortions (Table 3). Sometimes, however, it has been reported in a very high proportion of cases, usually combined with a high proportion of operations beyond the 12th week. Thus, Stallworthy et al. (27) in almost 800 cases terminated by uterine aspiration, report a blood loss of 500 ml or more in 17 % and haemorrhage requiring transfusion in 8 %. Infection shows the same distribution as the total complication rate. The very wide range reflects the great differences in the definition of infection, ranging from a temperature of 37.5°C to peritonitis. Incomplete evacuation of the uterus is the only complication reported slightly more often with uterine aspiration (24, 28, 30). Beric & Kupresanin (21) find the reverse to be true, but their two series are for different time periods and received different types of anaesthesia. Perforation of the uterus is infrequent, especially when uterine aspiration is used for induced abortion in countries with a high abortion load (21, 23, 26). In England several clinics using mainly this method (up to at least 14 weeks) report a perforation rate of 0.5-2.7% (18, 25, 27). Stallworthy et al. (27), during abdominal tubal ligation after uterine aspiration, found previously undiagnosed perforations in 3 patients. Treatment is usually laparotomy and repair or hysterectomy, but conservative treatment is often
successfully applied. In the JPSA study (15), of the 187 perforations reported 88 were handled successfully with conservative treatment. Cervical trauma parallels perforation, and is usually reported 3-5 times as frequently (15, 23, 26). Trauma to the uterine myometrium, defined as smooth muscular tissue found during histological analysis of scrapings from the uterine cavity, is frequently reported with dilatation and curettage, and Andreev (31) reports " deep injury to the muscular wall" (in his opinion carrying a serious risk of intrauterine adhesions) to be 38 times as frequent during dilatation and curettage as during uterine aspiration.
Second-trimester abortions Intrauterine instillation ofhypertonic solutions. The most extensive experience with this method so far has been in Scandinavia and lately in USA. In Japan it was formerly used extensively but not always with safety precautions, and the method has now been abandoned there because of high complication rates (32). The complication rates found in the JPSA study (33), a retrospective survey by Bengtsson (34), a consecutive series of 5 000 saline abortions by Kerenyi et al. (35), and an analysis of reports to the Danish Medical Health Board (6) are shown in Table 4. Bleeding is a much more frequent complication here than with first-trimester abortions. In Bengts-
ABORTION
son's study, which was based on an inquiry in all Swedish centres performing induced abortions, haemorrhage was said to have occurred when the patient received a blood transfusion. The fairly high rate of this complication probably reflects a generous attitude in Sweden towards replacing blood loss, but on the other hand there is evidence of a frequent decrease in coagulation factors after intra-amniotic saline instillations in otherwise uneventful cases (36-39). Infection is less common than haemorrhage, but is more frequently seen than with first-trimester methods (5, 33, 34). The incidence of infection following instillation of hypertonic glucose is usually higher than that following saline (5, 40). Retention of placental tissue is reported at extremely varying rates, owing to different attitudes of operating clinics. In many cases curettage is performed routinely after abortion. The failure rate is dependent to a great extent on the patience of doctors and patients but also on the solution used, the technique applied, etc. (discussed below). Schulman et al. (96), in inducing abortion by intrauterine saline injection in 323 outpatients, experienced only one failure (with a living fetus 3 weeks later), but 13 patients took more than a week to abort. Bengtsson (34) reports a rate of 96.5 % aborting after the first intra-amniotic instillation and 85.1 % after the first extra-amniotic instillation. The efficiency rate for the first intra-amniotic instillation in the JPSA study (15) was 95.5 %. Kerenyi et al. (35) give a corresponding figure of 98.6% success for the first instillation and 0.4% total failure for the last 1 000 patients in their series. Glucose is less efficient and failure rates of 15-22 % are reported (27). Symptoms of intravasal injection of hypertonic saline, sometimes combined with amnion embolism, are evident in a large proportion of case reports (6, 32, 34, 41, 42). The frequency of accidental transfusion is not known, but Gustavii (43), in 10 of 69 extra-amniotic instillations, by adding roentgen contrast medium could prove an immediate shift of fluid into the veins. Intravasal haemolysis (36), hypernatraemia (43, 44), and changes in blood volume (42, 44) have been seen, but marked changes seem to occur only in connexion with symptoms of intravenous injection. Hysterotomy and hysterectomy in the JPSA study (15), showed the highest complication rates of all methods: 38.0% and 51.2%, respectively; yet Olsen et al. (6) reported a complication rate of only 2.5 % for hysterotomy and sterilization in 6 544 cases.
127
However, all authors (6, 15, 18, 45) agree that the complications are definitely more serious. The reported incidence rates of " major " complications in connexion with hysterotomy and hysterectomy in local a JPSA patients are 9.4% and 17.1 %, respectively, compared with a total incidence of major complications of 1.6%. Vaginal hysterotomy, according to Lindahl (46), had a low immediate complication rate, but he found endometriosis in the scar in 19.8% of 840 follow-up cases. Other methods, such as soap, Utus paste, urea instillations, bougies, laminaria tents, and Rivanol, are used in some countries to a considerable extent but are usually very poorly reported, and the complication rates are difficult to estimate. For the period 1961-66, Olsen et al. (6) report 1 275 cases aborted with cremor saponis and a complication rate of 9.1 %-the highest produced by any method used in their series-and most European and American authors agree that the complications arising with the above-mentioned methods are more alarming (6, 45, 47-51). Rivanol 0.1 % given by extra-amniotic instillation is possibly more promising. The abortive effect is about the same as that of saline, it has a slight oxytocic effect in vitro (52), and the incidence of infection seems to be low (49, 52). It is claimed to be atoxic (used as a bladder disinfectant) and actually many of the fetuses are aborted alive. However, Pytel et al. (53) cite 4 cases of renal failure possibly related to the instillation of this solution. The numerous research projects on prostaglandins for the induction of abortion have been concerned mainly with the mechanisms of action and the effectiveness of various routes of administration. However, the substances also have pronounced systemic effects when administered by the intravenous, route. Anderson & Speroff (54) in a tolerance study infused PGF2a in doses of 25-200 jig/min in 10 patients. The incidence of nausea, vomiting, and diarrhoea was 90 %, 5 patients developed some degree of diastolic hypertension during infusion, and another developed a severe vasovagal shock and bradycardia lasting 45 min after the infusion was stopped. The techniques at present under investigation do not involve the intravenous route of administration. The intra-amniotic or extra-amniotic instillation of small amounts of prostaglandins (55-57) have increased the success rate and decreased the occurrence of side effects such as those mentioned above. a
Excluding patients residing outside the service area.
128
KARIN G. B. EDSTROM
The Task Force on the use of Prostaglandins for Regulation of Fertility is now working on finding the best techniques and compounds for induction of abortion. LATE SOMATIC SEQUELAE TO INDUCED ABORTION
A large number of late sequelae have been attributed to induced abortion, without any proved cause-relationship. Some sequelae have been studied more thoroughly than others-mostly those related either to the woman's ability to conceive after abortion or to the outcome of her subsequent pregnancies. Wynn & Wynn (58) in 1972 published a review on the side effects of induced abortion, containing a large part of all statements made against it and studies with adverse findings. This article has been much discussed in the United Kingdom and, among others, Trussell (59) and Potts & Shadbolt (60) have admirably pointed out the pitfalls in their reasoning. No gynaecologist who has performed an induced abortion ever tries to deny that it can give rise to early or late complications. But every gynaecologist also knows-which Wynn & Wynn seem to forget-that all other terminations of pregnancy, such as delivery or spontaneous abortion, also can produce the same type of complication. Furthermore, the fact that the woman applying for abortion is already pregnant must be accepted and taken into account when complications are discussed. All studies without adequate control groups (which here means comparable as regards both the previous number of pregnancies and the health and nutritional status) will show only that there are complications and not whether this way of terminating the pregnancy is more dangerous than letting it terminate by itself (or by clandestine abortion). This is unfortunately true of most retrospective studies published on this problem. Studies on psychiatric or emotional sequelae of induced abortion are not discussed in this paper. Such sequelae are too dependent upon national legislation and social attitudes to permit meaningful comparison of studies from different countries. The somatic sequelae most seriously investigated are discussed below. Reduced fecundity. Retrospective studies have sometimes blamed induced abortion as the cause of infertility (61, 62). However, Hayashi & Momose (63) compared a group of women complaining of secondary infertility with a group of multigravidae
delivered at full term and found no difference between the two groups in the proportion of women having experienced an abortion. The only exception was seen among those having experienced only one previous pregnancy, where the percentage of induced abortion among infertile women was 41.1 and that in the control group 32.6-a high incidence of aborted primigravidae also in the control group. In prospective studies by Lindahl (46), mainly involving vaginal hysterotomy, and by Jiratko et al. (64), probably covering primarily uterine aspiration, no definite evidence of reduced fecundity could be found. Premature births and spontaneous abortions in retrospective studies from Japan (65) occurred more frequently in women with previous induced abortions, among patients with premature deliveries, spontaneous abortions, or habitual abortions, than in control groups with full-term deliveries, but the latter were not matched according to age, social group, or parity. The same is true for Dol6zal et al. (66), who found a significantly higher proportion of previous induced abortions among 189 mothers with premature deliveries than in a control group of 197 women delivered of full-term babies. Other clinical studies also have shown an increased risk of premature delivery or second-trimester abortion after an induced abortion (67-69), but the control groups are usually never matched for both parity and health status, and it remains to be shown whether this increase is caused by the abortion procedure, by factors hidden in the decision to interrupt the pregnancy, or by both. Data from Hungary, where the incidence of low birth-weight is the highest in Europe, as is the incidence of abortion, seem to indicate that other factors also play an important role. In a survey in 1970 (70) they found that the rate of live-born babies weighing less than 2.5 kg increased with the number of previous induced abortions, there being a 100 % increase with 0-2 previous abortions and 200% at 4 abortions. However, the proportion of women with premature delivery but no previous abortion was also very high: 10.1 %, and the total percentage was 11.8. There was a successive increase from the 1960 percentages, but this was true also for women with no previous abortions, 8 % of whom that year had babies weighing less than 2.5 kg. During the same time the proportion of still births decreased at approximately the same rate as that of babies with low birth-weight increased. The Hungarian perinatal mortality study (71) showed the proportion with low
ABORTION
birth-weight to be higher in manual workers and in smokers than in nonmanual workers and nonsmokers, and the effect of these factors was apparently of at least the same magnitude. An increased frequency of extrauterine pregnancies has been mentioned by several authors, mainly from eastern Europe (30, 61, 72, 73). Cernoch (73) analyses the change in the numbers of ectopic pregnancies, induced abortions, and deliveries in Czechoslovakia in 1955-68, and he claims an increase in the former, parallel with the increase in induced abortions. During the years 1964-68, however, there is a decrease in the number of ectopic pregnancies in spite of a stable total number of pregnancies and a slight increase in induced abortions. Beric & Kupresanin (21) find, in Novi Sad from 1960 to 1970, an increase in the birth rate and in induced abortions but a relative decrease in the number of extrauterine pregnancies. Kur6iev et al. (72) report that 48.2% of the patients treated for extrauterine pregnancies in Skopje in 1967-68 had a previous induced abortion, but do not mention the abortion ratio in the population. Sawasaki & Tanaka (74), in 222 cases of extrauterine pregnancy among Japanese women, find that the preceding pregnancy was terminated by induced abortion in 43.8%, which does not differ significantly from the 50.2% found in a control group. The complication rate in subsequent pregnancies and deliveries, i.e., full-term deliveries, is also claimed to be affected by previous abortion. Thus, Lembryck (69), in his group of 143 primiparae (second gravidae) with a previous interrupted pregnancy, finds a higher frequency of bleeding during pregnancy and delivery and a somewhat longer first stage of labour, but a lower rate of toxaemia and no difference in the numbers of spontaneous deliveries. His control group consisted of 143 primiparae, primigravidae. Atanasov et al. (75) found 67.5% complicated pregnancies or deliveries in 265 women with previous abortions, compared with 13.4% in 418 with no previous abortion, the main complications being bleeding and toxaemia. He does not give data on parity in the two groups. Czeizel & Bognar (13), in a preliminary analysis of legal abortions in Hungary, found a rising incidence of deliveries complicated by placenta praevia and abruptio placentae that to some extent paralleled the rise in abortions. On the other hand, Heczko et al. (76) studied 173 parturient women who had had their first pregnancy terminated by abortion, and they found the same rate of late pregnancy and delivery complications
129
and the same perinatal mortality as among 18 226 other parturients during the same period. Furusawa & Koya (77) compared a large group of women terminating their first pregnancy by induced abortion and their second pregnancy by delivery with a control group of primiparae, primigravidae, matched for age and civil status. They found so significant difference in birth-weight, rate of instrumental deliveries, amount of bleeding, or length of the third stage of labour, although possibly a moderate increase in the length of the first and second stages in the group with previous abortions. Doleial et al. (66) did not find previous abortion more often in mothers giving birth to small-for-date children (
